What Is a Gi Jiu Jitsu? | The BJJ Uniform Explained

If you are new to Brazilian jiu-jitsu, the gi is the first thing you will notice on the mats. Adapted from the Japanese judo keikogi, this uniform is the standard gear for gi BJJ and is also commonly called a kimono. The thick fabric is not just tradition—it directly shapes how the sport is played, offering key differences from no-gi grappling.

Understanding the gi’s parts and purpose is essential before your first class.

The Three Main Components of a BJJ Gi

Every gi features the same core parts, each with a specific role. The jacket, pants, and belt are all designed to handle the rigors of intense training and gripping.

• The Jacket: This is the heavy cotton or cotton-like weave top. Its collar, sleeves, and lapels are the primary targets for grips that control your opponent’s posture and movement.
• The Pants: Reinforced at the knees and seat, the pants are built to survive constant dragging and pressure. Opponents will grip the pant legs at the cuff to break your balance and pass your guard.
• The Belt: Wrapped around the waist to secure the jacket, the belt indicates the wearer’s rank within the art. It also serves as a viable grip for many techniques.

Why the Fabric Changes the Game

The gi’s fabric creates friction and offers numerous grip opportunities, enabling a control-based style that differs significantly from no-gi grappling. In jiu-jitsu, practitioners grip the collar, sleeves, and pant legs to control posture, break balance, pass guard, and set up submissions and sweeps. The fabric allows for slower, more methodical positional exchanges where strategic grip fighting is crucial. You might be surprised to learn that a good gi purchase starts with the right fit.

IBJJF Competition Rules You Should Know

If you plan to compete under the International Brazilian Jiu-Jitsu Federation (IBJJF), there are strict rules about what you can wear. The IBJJF uniform page states that only white, royal blue, or black gis are allowed, and the jacket, pants, and collar must match the permitted color scheme. The gi must be in good condition and not so thick that it prevents an opponent from gripping it.

Proper fit is also checked at official events. According to IBJJF guidelines, the jacket top should reach your thigh, and the sleeves should come to no more than 2 cm from your wrist when your arm is extended parallel to the ground. Pants must fall within a similar limit relative to the ankle bone. A gi that is too thick, too short, or in the wrong color will fail inspection.

Since gi rules are competition-specific, your local training gym may allow a wider range of colors, patches, and materials than IBJJF rules do. Always confirm your federation’s requirements before competing.

If you are ready to start training, finding the right gear is the first step. Check out our tested roundup of the best women’s Brazilian jiu-jitsu gi options.